Mason Jar Science Experiments for Kids

Mason jars are incredibly handy for classroom science experiments. They're clear, durable, and easy to find, making them perfect for observing changes, layering materials, or creating closed environments. Teachers looking for hands-on, low-cost ways to spark curiosity in students of all ages can use glass Mason jars to bring a wide range of scientific concepts to life. Whether you're teaching young kids about basic chemistry or helping teens explore environmental science, these simple glass containers offer big potential.

Elementary-Level Science Experiments

Kids love the dancing raisins experiment. To do it, fill a Mason jar with clear soda like Sprite or 7UP. Drop in a few raisins and watch them rise and fall. This fun activity introduces the concept of buoyancy and carbonation, helping kids see how gas bubbles attach to the raisins and make them float.

You could also explore density by making a rainbow in a jar. Using sugar water with different concentrations of sugar or other liquids with a variety of densities, kids can carefully layer liquids of different colors inside a Mason jar to create a rainbow.

When it's time to teach your students about how plants grow, line a Mason jar with a wet paper towel and place a few seeds (like beans) between the towel and the glass. Kids can observe daily changes as the seeds sprout.

A Mason jar is also a great container for a chemical reaction. Fill a glass jar with baking soda, a few drops of food coloring, and some dish soap, then add vinegar and watch the "volcano" erupt!

You can also teach kids about the water cycle using a jar. Add a small amount of water to a Mason jar, seal it tightly, and place it in a sunny spot. Over time, kids can see condensation and precipitation form inside the jar, making it easier to understand how the water cycle works.

• Dancing Raisins: Read an outline of this simple experiment here.
• Rainbow in a Jar: Sugar water solutions are the basis for this density experiment.
• Beans in a Jar Science Experiment: Germinating seeds is simple to do with little more than a jar and a paper towel.
• Volcano Experiment: If you want to add a bit more fun to this experiment, have the kids build a volcano around the jar using playground sand or snow.
• Water Cycle in a Jar: All you need is a jar and some water to get started with this activity.

Middle School Science Experiments

Mason jars make good containers for crystal-growing experiments. Mix hot water and borax in a Mason jar to create a supersaturated solution, then suspend a pipe cleaner from a pencil laid across the top. Let it sit overnight and see how crystals form.

Kids can also learn about emulsions with simple glass jars. Just pour oil and water into a Mason jar, then add food coloring and a drop of dish soap. Shake it up and observe the emulsion before it separates again. This is a great introduction to polarity and how surfactants work.

Combine water, oil, and food coloring in a Mason jar and add an Alka-Seltzer tablet for another fun experiment. The bubbling motion shows density differences and gas formation in action in a way that's mesmerizing and easy to understand.

Place steel wool in a Mason jar with a little vinegar and seal it for a lesson on how rust works. Students can observe rust forming over the next few days. This experiment is ideal for when you're discussing oxidation and chemical change.

You can also experiment with air pressure and combustion in a jar. Put a lit candle on a plate, and then pour water onto the plate. Invert the jar and cover the candle, then watch the water rise once the candle goes out.

• Growing Borax Crystals: Students can learn about how crystals form using this common cleaning product.
• Making an Emulsion: Oil and water usually don't mix, but an emulsifier can help them blend together.
• Make an Alka-Seltzer Lava Lamp: This experiment creates a cool-looking reaction!
• Steel Wool in Vinegar: In this video, the Sci Guys explore the science of oxidation.
• Classic Candle Experiment: Water rises into the jar like magic, but it's really just science.

High School Science Experiments

Take the water cycle in a jar to the next level by creating terrariums. Make a mini ecosystem by adding soil, small plants, and water to a Mason jar. Seal it and observe how it sustains itself over time. This experiment helps students understand balance, photosynthesis, and ecological systems.

Students can also do a bit of culinary and biological experimentation by using Mason jars to ferment sugar water with yeast. Attach a balloon to the top to measure the gas production. This is useful for studying cellular respiration, anaerobic processes, and biofuel concepts.

Using red cabbage juice as a pH indicator is a great high school science experiment you can do in a Mason jar. Students can add different household liquids to test acidity and alkalinity. The color changes make the pH scale visually engaging.

If you're teaching Earth science, layer gravel, sand, and activated charcoal in a small plastic cup, poke a hole in the bottom, and place it inside a Mason jar to create a water filtration system. Pour dirty water into the cup and collect the filtered water as it trickles out into the jar. This practical demonstration connects with lessons about environmental science and water treatment.

Cell biology can also be the subject of a Mason jar experiment. Place slices of potato in jars of salt water with different salt concentrations and observe them over time. This helps students understand how solutes and water move across cell membranes.

• How to Make a Mason Jar Terrarium: Follow these steps to build a miniature ecosystem in a jar or bottle.
• Blow Up a Balloon With Yeast: When yeast consume sugar, they release carbon dioxide gas.
• Red Cabbage Juice Indicator: Once you make this indicator solution, you can divide it between different jars to perform pH tests.
• Water Filtration: Learn how to set up a water filtration experiment in a jar.
• Osmosis in Potato Slices: Students can see how salt concentrations affect the migration of water through cell membranes in this experiment.